Abstract: Natural space radiation such as that found in the Van Allen belts （electrons and protons） inflicts ionizing dose damage on semiconductor devices. This damage degrades the performance of many types of semiconductor. Consequently, the life of important military and commercial missions is shortened. A simple and direct way to lengthen the life of semiconductor is to shield them against the energetic radiation particle environment. Electrons and protons can be shielded effectively, while energetic heavy ions and gamma radiation are difficult to shield. The secondary package technique of compositing material of 54HCT00 CMOS device is adopted and experimental circuit of device is designed in this paper. Devices on bias are irradiated by electron source and results are obtained with the help of measurement on line. The level of ionizing dose is increased by 1-2 order of magnitude using secondary package. The anticipated data and results are achieved. An approach is provided to exploit space application for commercial semiconductor device.